Automatic brake-adjusting mechanism



Patented Mar. 6, 1928.

UNITED STATES 1,661,191 PATENT OFFICE.

GABRIEL MIDBOE, 0F BROOKLYN, NEW YORK, ASSIGNOR TO INTERNATIONAL MOTORCOMPANY, OF NEW YORK, N. Y.,

A CORPORATION OF DELAWARE.

AUTOMATIC BRAKE-ADJUSTING MECHANISM.

Application filed January 8, 1927. Serial No. 159,830.

This invention relates to brake adjusting mechanisms, particularly thoseapplicable to the service and emergency braking systems found on mostvehicles of today. It is wellknown that the difliculty of maintainingthe several brakes disposed upon the respective wheels of the vehicle inad ustment has presented a problem, the solution of which has not beeneffectively accomplished as yet. Y

An object of the present invent1on is to provide an automatic means foradjusting each individual brake upon the reaching of a predetermineddegree of mal-adjustment of the brake to be adjusted.

A further object of this invention is to construct the automaticadjusting mechanism above referred to in a convenient and effectiveposition in the line of brake operating mechanism.

Reference will now be had to the accompanying drawings forming a parthereor for a more detailed description of the invention, wherein:

Figure 1 represents an elevation, partly in section, of a preferred formof the invention.

Figure 2 is a side elevation with the automatic adjusting means shown indotted lines.

In the drawings, a designates the brake cam shaft upon which is keyed orsplined as at a a worm wheel b. The brake lever 0, connected to thebrake rod d, is provided with a housing 0 andbearing portions 0 whichpermit the lever to move upon the cam shaft a. In the upper portion ofthe housing 0, a hollowed out, cylindrical, section 0 is provided,within whichiworm e is carried. Nuts f, f are adapted to be secured ateither ends of the cylindrical portion 0 and serve as hearing membersfor a shaft 0' which carries the'worm e, and which rotates therewith.

On the projecting portion of the shaft 0' and outside of the cylindricalportion 0 is keyed a hub g which is provided with ratchet teeth g, thehub having bearing surfaces 9 on either side of the teeth g. An arm h,provided with an annular portion It, one side of which bears upon onebearing portion 2 and the other side of which is adapted to receive aclosure h threaded thereinto, houses the ratchet portions g. Within thedownwardly extending portion of the arm h, a pawl 73 is carried, aspring 11 seated by a suitable screw 7? serving to urge the pawl intoengagement with the teeth 9 of the ratchet wheel. Extending laterallyfrom the arm h is a portion h the movement of which is limited by lugs3" formed upon the housing j which receives the cam shaft a. A nut esecures the bracket h and associated mechanism to the shaft 6'.

The operation of the device is as follows: when the brake is inadjustment, movement of the brake rod cl to apply the brakes causesrelative movement between lever c and housing 7'. The worm and wormwheel being made with a very small helix angle, the relative position ofthe cam. and lever will remain unchanged. By rotating the worm this canbe changed, and the wear of the brake lining can be compensated fromtime to time as is found necessary. Should the brake be out ofadjustment an excessive movement of lever 0 will be required, and thelateral extension 72, will engage one of the lugs j, it being understoodthat the lugs are positioned upon the housing j so that they will not beengaged by the element It as long as the brake is in proper condition.In the continued movement of the lever 0 after the element 72, hasengaged a lug j the arm 72, together with the pawl 2', will turn withrespect to the ratchet wheel g. Further movement in the application ofthe brake will cause the pawl to ride over the next tooth in the ratchetwheel and upon the return of the lever 0, the cam 0 will be turned tovary the position of lever c with respect to the brake cam. It isobvious that the position of the cam with re spect to the lever 0 willbe varied as the wear on the brake band increases, and in housing, aWorm wheel carried by the applyupon the first named mounting means, said10 ing means and received within the first housarm extending between thelugs whereby ing, a shaft transverse to the applying means predeterminedmovement of the lever with and carried by the second housing, a Wormrespect to the mounting means causes the mounted on the second shaft andengaging arm to engage a lug to effect the operation the worm Wheel, aratchet and pawl mechaof the ratchet mechanism. nism carried by thesecond shaft outside the This specification signed this 6th day ofsecond housing, an arm carried by the January, A. D. 1927.

ratchet and pawl device, and spaced lugs GABRIEL MIDBOE.

